# Relationship history for MSHA mine 3606622

Current hierarchy: **Myers William H → Myers Coal Company → Poplar Run Strip**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** Myers Coal Company → Poplar Run Strip; 1978-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Myers William H → Poplar Run Strip; 1978-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Myers William H → Myers Coal Company; 1978-03-01 to current/open; source msha-controller-operator-history